This invention relates to the field of numerically-controlled machine tool accessories, machining centers, and flexible cells and workshops, and it has as its object a damping means for tool holders, such as a boring head, a chuck or a milling cutting arbor.
The tool holders have a tendency, from the very fact of their composition, to vibrate, which is detrimental to their proper operation. This tendency to vibrate is all the more significant since the actual operating speeds of the machine tools are increasing constantly.
To prevent these drawbacks, it was proposed to equip the tool holders with a device for damping oscillations, making possible an adaptation of their rigidity to the operating conditions.
For this purpose, such a device that essentially consists of a damping mass mounted in an axial housing and clamped in the latter between elastically deformable masses, with the adjustment of the stiffness being done by means of a spring-loaded stop means, where the setting of this spring itself can be regulated by means of a screw device, is currently known in particular from U.S. Pat. No. 3,447,402.
Furthermore, an adjustable shock absorber for machine tools that consists of a damping element placed in an axial hole of a tool holder shaft and connected to this shaft by means of annular elastic elements, mounted on conical ends of the damping element and able to be compressed on said ends so as to regulate the rigidity, is known from FR-A-2 173 957.